1. Field of the Invention
The present invention relates to autoloading firearms. More specifically, the invention is an apparatus for tuning the gas flow rate and/or timing of an autoloading firearm for different operating conditions.
2. Description of the Related Art
In the field of autoloading firearms, adjustable gas blocks provide means for compensating for regulated gas flow attributable to the use of silencers and various types of loads of ammunition. It is known, for example, that the addition of more gas into the operating systems increases the potential for failure of the autoloading mechanism. Particularly with high-precision autoloading firearms, the ability to fine tune the gas flow characteristics becomes even more important, as even minor differences between ammunition can affect the efficiency of the operation of the autoloading mechanisms.
One patent that shows a system of adjusting gas flow characteristics is U.S. Pat. No. 7,856,917, issued Dec. 28, 2010 to Noveske, which is incorporated by reference herein. Noveske discloses an improved switchblock for use in autoloading firearms that facilitates user adjustment of the gas output. Noting that other designs, such as the ArmaLite AR10 gas block, offer the user the ability to regulate gas flow by toggling a screw between only two positions, Noveske offers three such positions of adjustment: a standard gas flow optimized for a firearm, a reduced gas flow optimized for the firearm when used with a suppressor, and a no-flow position which completely shuts off gas flow.
Other manufacturers offer products that provide the ability to “micro” tune gas flow. For example, Spike Tactical LLC of Apopka, Fla. and JP Enterprises, Inc. of Hug, Minn. offer an adjustable gas block that relies moving a set screw into and out of the volume of the gas block in a direction other than parallel to the longitudinal axis of the volume. Spike Tactical's product is sold under the tradename SUGB130. JP Enterprises's product is sold under the tradename JP Adjustable Gas System.
While Noveske, ArmaLite, Spike Tactical, and JP Enterprises represent improvements over other systems that do not provide a mechanism for adjusting gas flow characteristics, Noveske does not provide fine, indiscrete tuning of such characteristics. And even when providing adjustable positions for regulating, existing systems introduce gas into the gas chamber in a highly turbulent manner that directs the gas directly toward a surface of the gas chamber. This causes the gas to immediately lose significant amount energy while turning ninety-degrees toward the piston assembly, and negatively affects the gas-cyclic efficiency and overall performance of the autoloading firearm.
For high-precision firearms, the pressure and volume flow-rate required to actuate the piston, and thus cause reloading of the firearm, must fall within a given range. When using different bullet types, weights, and load charges, the pressures created by the bullet discharge may fall outside that range, effectively meaning that the firearm will not properly cycle with all loads. Systems such as Noveske, however, do not provide the user with the ability for tuning of the auto-loading mechanism of such high-precision firearms.